Overrunning clutch and control means therefor



Dec. 8, 1936. J. w. HOBBS V OVERRUNNING CLUTCH AND CONTROL MEANSTHEREFOR Filed March 27, 1951 5 Sheets-Sheet l v irr II 4 1-2 YEW/Er JraZflflos.

Dec. 8, 1936. J. w. HOBBS OVERRUNNING CLUTCH AND CONTROL MEANS THEREFOli 5 Sheets-Sheet 2 Dec. 8, 1936. J. w. HOBBS QVERRUNNING CLUTCH ANDCONTROL MEANS THEREFOR Filed March 27, 1931 5 Sheets-Sheet 5 PatentedDec. 8, 1936 UNITED STATES OVERRUNNING CLUTCH AND CONTROL MEANS THEREFORJohn W. Hobbs, Chicago, Ill., assignor, by mesne assignments,

to Borg-Warner Corporation,

Chicago, 111., a, corporation of Illinois Application March 27, 1931,Serial No. 525,737 14 Claims. (Cl. 192-43) This invention relates tomotor vehicle transmissions, and has generally to do with an overrunningdrive and lock-out mechanism therefor.

In constructions of this character heretofore in vogue, that is,employing mechanism permitting the vehicle to proceed by virtue of itsown momentum independently of the engine, so that the latter will not berun unnecessarily and will not act as a brake, means have been providedfor locking-out the overrunning elements so that the engine will act asa brake when desired. As heretofore employed, such means, whileperforming a desirable function, have been in one manner or otherunsatisfactory.

The reason for the dissatisfaction growing out of the use 01 the presenttype of lock-out mechanism resides in the fact that such mechanism isoperated by means of an extra lever placed within reach of the driver.It will be appreciated that when it is the desire of the driver to bringthe car to a stop, or at least to employ the engine as a brake tosubstantially slow down the car, which desire manifests itselfparticularly in case of an emergency, the driver has all he can do toproperly steer the car with his hands without subjecting himself toextra effort to lock-out the overrunning mechanism. In the case 'ofpresent structures having this function, a lever is provided and theoperator must move into an unnatural position to lock-out theoverrunning device, and this is dangerous as well as annoying since itoccurs at a time when all his attention should be focussed on the roadand the proper driving and steering of the car. In addition to theannoyance resulting-from his necessarily assuming an awkward positionwith constructions heretofore in use, it often proves to be quitedangerous.

It is accordingly one of the objects of the 40 present invention toprovide a device for rendering the overrunning instrumentalities of a.

55 dering ineffective the overrunning mechanism of Y a. vehicle, inconsequence of a normal vehicle retarding act of the driver.

Another object resides in the provision of means operable in response tomovement of the clutch and brake pedals of a motor vehicle to 5 renderthe overrunning instrumentalities thereof ineffective.

Another object of the inventionfis to provide means for rendering theoverrunning instrumentalities of a motor vehicle ineffective without ap-1o preciable shock to the parts. i,

It is another object of the invention to provide spring means pressingspaced portions ofeach roller of an overrunning clutch to precludetilting of the rollers and insure their proper 811- 15 gagement with theoverrunning parts.'

Further objects and advantages of the present invention will appear asthe description proceeds.

In carrying out the invention, I avail. 'm'yself of any suitable driveelement such as a fl'ywli'eel' and associated back and pressureplateoonstruction for cooperation with the enginei clutch facings. Theclutch is of a special character embodying overrunm'ng parts, one of theparts being splined to the usual driven element such as 1. splinedshaft, and the other part having locking teeth. A sleeve on the shaft isoperable by the clutch pedal for disengaging the clutch. A second sleeveis mounted for movement on the spline shaft in response to movement ofthe brake 30 pedal. This second sleeve is provided with teeth adapted tointerlock with the toothed part of the clutch to thereby lock theoverrunning parts against relative movement so that the engine will actas a brake. Suitable mechanism is pro- 35 vided in connection with thebrake and clutch pedals and is of such construction that it will permitthe brake pedal to actuate the usual wheel brake means of the vehicle,but will not permit. locking of the overrunning parts unless the 40clutch pedal has first been depressed a certain amount. Thus, when thedriver desires to momentarily reduce the velocity of the vehicle, thatis, when he desires to make use of the wheel brakes only, he may simplydepress the brake lever and the desired result will be accomplished.However, whenhe desires the use of the engine to brake or retard thecar, he will depress both the clutch pedal and the brake pedal,whereupon the teeth on the second sleeve will engage the teeth on theclutch and thereby establish adirect two-way connection between thedrive and driven shafts of the vehicle. If necessary, the engine clutchmay be disengaged to avoid clashing of the teeth.

It will thus be apparent that the hands of the driver are not necessaryto the actuation of the mechanism herein set forth, so that he is notsub- Ject to the annoyance caused by being required to assume an awkwardposition, as in the case of hand lever controlled lock-out devicesheretofore in vogue, and in addition it will be noted that it isnecessary that the operator perform a normal act in order to takeadvantage of the engine as a braking means.

on the drawings:

Figure 1 is a fragmentary sectional view showing an embodiment of theinvention.

Figure 2 is a view of the overrunning construction taken approximatelyin the plane indicated by the line II-II in Figure 1, slightly brokenaway to show a detail.

Figure 3 is a fragmentary side elevation showing the special mechanismby means of whichthe overrunning parts are locked, the parts beingarranged in inoperative position.

Figure 4 is an enlarged fragmentary side elevation of the mechanismshown in Figure 3.

Figure 5 is a view similar to Figure 4, but showing the operating partsin their relative positions when the overrunning device is locked-out.

Figure 6 is a fragmentary plan view of the parts as they appear inFigure 4.

Referring now more particularly to the drawings, wherein the same partsare indicated by the same reference characters, a flywheel I is providedwith a back plate 2 secured thereto in any suitable manner, and withopenings 3 for the reception of bolts to secure a crank shaft (notshown) thereto. A splined shaft 4 having an end rotatable within the'flywheel I carries a clutch 5 provided with facings 6 which areyieldably maintained in driving contact with the cooperating surfaces ofthe flywheel I and the pressure plate I by spring means not shown.Pressure plate retracting levers 8, one of which appears in thedrawings, are actuated by a slidable sleeve 9, play being provided at Ibetween the sleeve 9 and the levers 8. The clutch retracting sleeve 9 isactuated in the usual manner in response to depression of the clutchpedal II mounted on and causing rotation of the stud I2, the latterbeing provided with a lever I3 connected with the sleeve 9.

In accordance with the present invention, instead of making the clutch arigid member, as in prior constructions, thesarne is made of a pluralityof parts, the outer of which, indicated at I4, carries the clutchfacings. The inner part or hub i5 is splined on the spline shaft i,which is a driven shaft, and spring pressed rollers i6 carried inconverging grooves provided by the parts I4 and provide an overrunningdrive between these parts. In order to insure proper gripping of therollers l6, each is urged toward the small part of its recess by a pairof springs 17, one adjacent each end of the roller. The two springs holdthe rollers in alignment and obviate tilting thereof which hasheretofore caused faulty operation where only a single spring wasemployed. Bearing in mind that the arrangement shown in Figure 2 istaken approximately in the plane of the line IIII of Figure 1, it willbe clear that the hub I5 is capable of movement relative to the outerpart I4 so that a motor vehicle embodying able to use the engine for thepurpose of braking the vehicle, and to this end the outer part I4 of theclutch 5 carries a ring I9 provided with a series of internal teeth I9.Splined on the shaft 4 is a sleeve disposed preferably within the sleeve9 and, provided with external teeth 2| adapted for interlockingengagement with the teeth I9 carried by the part I4. The sleeve 20 isoperably connected to a stud 22 through the medium of a lever 23, saidstud being adapted to be actuated in response to depression of the brakepedal 24 in a manner to appear hereinafter. Thus when the sleeve 20 isactuated in a direction toward the clutch 5, the teeth I9 and 2| willinterlock to thereby set up a direct two-way driv.e between the flywheelI and the driven shaft 4, so that the engine, being connected to theflywheel I, will serve as a brake for the vehicle when the speed of thedriven shaft 4 tends to exceed that of the flywheel.

In accordance with the present invention, unique instrumentalities areprovided for the purpose of permitting the use of the foot brake toresist movement of the vehicle when it is not desired to employ theengine as a brake, yet being so operable as to bring the engine into useas a brake when such use of the engine becomes desirable. To this end,the stud 22 is extended through the casing 44 and carries for movementtherewith a lever 25. A rod 26 passes through the lever 25 and hasuniversal movement with respect to the lever as indicated at 21. Therear end of the rod 26 carries an abutment 29, and a spring 29 is heldbetween the lever 25 and the abutment 28. If desired, a washer 30 may bearranged between the spring 29 and the lever 25. An abutment 3| is alsoprovided on the rod 26 but on the other side of the lever 25 and isconnected to. the rod in order to limit movement of the latterrearwardly with respect to the lever 25. The forward end of the rod 26is joined to the brake pedal 24 by a swivel connection 32, in order thatthe rod 26 may be drawn forward in response to depression of the brakelever 24. A further abutment 33 is adjustable on the end of the rod 26and is resiliently maintained in engagement with the swivel connection32 by the usual brake pullback spring means, such as the spring 25aacting on the brake linkage, a part of which is shown at A. It is notedthat the various abutments are adjustable to vary the pressure of thespring 29 and the distances between the abutments.

The clutch pedal has swiveled thereto at 34 a second rod 35 having alost motion pivotal conneetion at 36 with a bell'crank catch lever 31. Aspring 33 constantly urges the lever 31 to move in a counter-clockwisedirection as viewed in Figures 3, 4 and 5. The lever 31 is pivotallycarried by a stud 38a and is provided with an adjustable stop 39 adaptedto cooperate with the portion 40 of the lever 25 to limit movement ofthe latter.

The rod 26 is connected in any suitable manner, .such as shown in Figure1, to the wheel brake operating means, a part of which appears at A. Itwill be noted that this rod is movable forward in response to anydepression of the brake lever 24 to thereby actuate the wheel brakes(not shown) and that said brakes are returned to released positions bymeans comprising the spring 25a, which also returns the rod 26 and lever25 upon release of the brake pedal 24.

The Operation 0! my construction is as follows: Assume the various partsto be arranged as shown in Figure l, and that the vehicle is coasting,the spline shaft 4 rotating at a greater speed than the flywheel I sothat the hub l5 overruns or moves relative to the outer part I of theclutch 5, and that the driver desires to apply only. the foot brake.Directing our attention particularly to Figure 4, it will be seen thatforward movement of the brake pedal will result in movement of the rod26 and hence operation of the wheel brakm, while corresponding movementof the lever 25 is prevented by the shoulder II on the lever 31, thebrake lever being suitablyj connected with the wheel brakeinstrumentalities of the vehicle to operate the same.

Should the operator desire to connect the engine to the driven shaft insuch a manner that the overrunning parts will be locked, so that theengine will act as a brake, it is necessary, in addition to depressingthe brake lever 24; to also depress the clutch pedal H suilicientiy tobring the shoulder ll of the lever 37 below the lower portion 40 of thelever 25 so that the spring 29 can force the lever 25 forward. When thisis done, the stud 22 is caused to rotate, whereupon, as seen in Figure1', the sleeve 20 will be urged forward by the lever 23 with the resultthat the teeth 2! willinterlock with the teeth i9. Once the lever 25 ispermitted to move forward beyond the shoulder 41. the driver releasespressure on the clutch pedal and the latter will be brought by the usualspring (not shown) to its normal position as seen in Figures 1 and 2 andin dotted lines in Figure 5. Then, as long as the foot brake pedal isheld in a depressed position, the engine will serve as a brake to reducethe speed of the vehicle when the driven shaft 4 tends to move at agreater speed than the flywheel I.

Figures 1 and 2 show the clutch and brake pedals in their normalpositions, and Figure 5 shows, in full lines, the arrangement of theparts when both pedals are depressed as mentioned. It will be noted thatthe play I!) between the sleeve 9 and the levers 8 is of such extentthat the sleeve 9 will not depress the levers 8 during the slightdepressing movement of the clutch pedal necessary to release the lever25. Inasmuch as the sleeve 8 is movable independently of the sleeve 20,it will be seen that the act of disengaging the clutch may be performedin the usual way. It will be noted, however, that the block 42 carryingthe spring 38 is located asufflcient distance from the arm 43 of thelever 31 to permit the arm 43 to be swung in a clockwise direction to asuilicient extent to permit complete depression of the clutch lever IIwhen it is desired to disengage the clutch.

The engine clutch pedal ii is operative in the usual way to effectdisengagement of the engine clutch. It will be observed that thisoperation may take place regardless of the position of the.

overrunning clutch lockout lever 25, since the latter will not interferewith the consequent clockwise turning of the bellcrank lever 31. Sincethe wheel brakes will be in released condition when it is desired toreengage the engine clutch, the usual wheel brake spring means (notshown) acting through the. rod 28 as pointed out above will hold thelever 25 in retracted position as shown in Figures 3 and4, where saidlever will not interfere with the return movement of the bellcrank lever31 under the influence of the spring 38. The nuts 3! may be shiftedtoward the nut 28 to vary the clearance between the shoulders 40 and H.

It will be appreciated .from the foregoing that with this invention thewheel brake and engine clutch may be controlled independently of eachother as in a conventional car, that energy for locking out theoverrunning clutch is stored up. by virtue of the .application of thebrakes, and

that this energy may be released by movement of the clutch pedal withoutnecessitating disengagement of the engine clutch although'the 'lattermay be eifected to avoid clashing of the varied through a wide rangewithout departing from the principles of this invention, and I,therefore, do not purpose limiting the patent granted hereon otherwisethan necessitated by the prior art. a

I claim as follows:

1. A motor vehicle having clutch and brake members, a driving element, adriven element, an overrunning connection between said elements,means'operable by said brake member for pre-, venting overrunning ofsaid connection, and means controlled by the clutch member to preventlocking-out of said connection when said brake member is operated. 1

2. A motor vehicle having clutch and brake pedals, a drive element, adriven element, overrunning parts connecting said elements, meansincluding a lost motion connection associated with said clutch pedal sothat the latter may be depressed to a certain extent without disengagingthe clutch, means associated with said brake pedal for locking saidoverrunning parts, and

including a lost motion connection cooperating with the first lostmotion connection, and means controlled by said clutch pedal to, resistoperation of said locking means.

3. A motor vehicle including a brake pedal, a clutch having overrunningparts,a clutch pedal, a rod connected to said brake pedal, a levermovably connected to said rod, means limiting relative movement of saidlever and rod, a spring urging said lever toward said means, a catch toprevent movement of said lever when said brake pedal is depressed,whereby the brake is operable independently of said lever, said catchbeing controlled by said clutch pedal so as to be retracted thereby andpermit movement of said lever, said catch being retained in retractedposition by said lever when the brake pedal is depressed, so thatpressure on said clutch pedal may be released, and instrumentalitiescontrolled by said lever to cck said overrunning parts against relativemovement.

4. A motor vehicle including a brake pedal, a clutch having overrunningparts, a clutch pedal, a rod connected to said brake pedal, a levermovably connected to said rod, means limiting relasaidoverrunning partsagainst relative movement, 'a driven element carrying said clutch, aslidable sleeve about said element and operatively associated with saidclutch pedal for disengaging said clutch, said'instrumentalities including a second slidable sleeve about said element, and interlockablemeans on said clutch and second sleeve.

5. A motor vehicle including a brake pedal, a clutch having overrunningparts, a clutch pedal, a rodconnected to said brake pedal, a levermovably connected to said rod, means limiting relative movement oi.saidlever and rod, a spring urging said lever toward said means, a catch toprevent movement of said lever when said brake pedal is depressed,whereby the brake is operable independently of said lever, said catchbeingv controlled .by said clutch pedal so as to be retracted therebyand permit movement of said lever, said catch being retained inretracted position by said lever when the brake pedal is depressed, sothat pressure on said clutch pedal may be released, instrumentalitiescontrolled by said lever to lock said overrunning parts against relativemovement, a driven element carrying said clutch, said instrum'entalitiesincluding a slidable sleeve about said element, and interlockable meanson said clutch and sleeve.

6. In a motor vehicle, a driving element, a driven element, anoverrunning clutch connecting said elements, means for establishing atwo-way drive between said elements, means for storing up energy tooperate the first means, anda device for releasing said energy.

7. In a motor vehicle having a brake, driving and driven elements, anoverrunning clutch connecting said elements, means for interlocking saidelements to establish' a two-way drive therebe tween, means for applyingthe brake and at the same time storing up energy for operating theinterlocking means, and means for releasing said energy. I

8. In a motor vehicle having a brake, driving 1 and driven elements, anoverrunning connection therebetween, means for applying the brake andsimultaneously establishing a two-way drive between said elements, andmeans for preventing establishment of said two-way drive withoutinterfering with the application of said brake.

9. A motor vehicle having means accessible to the driver for controllingthe transmission of power and for braking the vehicle, a drive elementof said vehicle, a driven element, an over-running connecton betweensaid elements, and instrumentalities independent of said connection andoperable in response to the combined actuation of said controlling andbraking means by the driver for preventing over-running of saidconnection.

aooaavo 10. A motor vehicle having means accessible to the driveriorco'ntrolling the application of power and for braking the vehicle,driving and driven elements 0! said vehicle, a one-way clutch interposedbetween said elements, means for converting .said one-way clutch into atwo-way drive, and

means for operating said last mentioned means in response to thecombined actuation of said controlling and braking means by theoperator.

11. A motor vehicle including a drive element, a driven element,overrunning parts connecting said elements, means for locking said partsagainst overrunning, spring means for actuating and facilitatingoperation of said locking means, a driver-controlled devicefor-energizing said spring means, and means arranged to optionallyprevent actuation 01 said locking means when said spring means isenergized.

12. A motor vehicle including a drive element, a driven element,overrunning parts connecting said elements, means for locking said partsagainst ing m'eans, means for locking said overrunning parts together,brake operating means controlling said locking means, and means forpreventing actuation of the locking means before the clutch disengagingmeans is actuated.

14. In a motor vehicle having a driving element and a driven element,mechanism comprising, a manually operable brake control member for saidvehicle, a second manually operable control member {or said vehicle, anoverrunning clutch connectingsaid driving element with said drivenelement, a positive jawclutch adapted when rendered effective to lockout said overrunning clutch, means through which said positive clutchmay be rendered efiective upon manua1 operation of said brake member ina direction to apply the vehicle brakes, and other means associated withsaid first named means and with said second control member so arrangedas to compel operation of said second control member prior to theoperation of said positive jaw clutch to lock out said overrunningclutch in response to manual operation of the brake control member asaforesaid. v

JOHN W. HOBBS.

